Process of manufacturing certain lead products.



PROCESS 0f MANUFACTURING CERTAIN LEAD PRODUCTS.

APPucATmN 111.51; 1128.15.1915. RENEwED FEB. 5, 1919.

1,297,934. Y 4 Patented Mar. v18, 1919.

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UNITED STATES PATENT oEEIcE.

WILLIAM P. THOMPSON, or' LIVERPOOL, ENGLAND.

PROCESS OF MANUFACTURING CERTAIN LEAD PRODUCTS.

Specification of Letters Patent.

Patented Mar. 18, 1919.

Application led February 6, 1915, Serial No. 6,607. Renewed February 5, 1919. Serial No. 275,199.

. Tb all whom t may concern.'

Be it known that I, WILLIAM PHILLIPS THOMPSON, a subject of the King of Great Britain, residing at Liverpool, in the county of Lancaster, in the Kingdom of England, have invented certain new and useful Improvements in Processes of Manufacturing Certain Lead Products, f which the following is a specification.

This invention has for itsprincipal object a very simple method of making white lead (hydro-carbonate of lead) from lead without touching the material from the time it is metallic lead, to the time when it is' completely formed hydro-carbonate of lead, and

at the same time producing a hydro-carbonate of VVlead almost if not quite equal to. that produced by the Dutch process, but in j a vastly shorter time, and also if desired .an intermediate roduct, pure or slightly thydrated finely ivided non-crystalline monoXid of lead.

The invention is best described by aidpof the accompanying drawings, in which:

Figure l shows a somewhat diagrammatic longitudinal vertical section of. my preferred form 'of apparatus.

Fig. 2 is a cross sectional view of'same, looking from the right of Fig. 1 with the chimney, oxidizing devices, the conveyer, the acetic acid chamber, the fan and air-heating pipes omitted.

Fig. 3 is an enlarged vertical section of the aspirating device and `chamber on same plane as Fig. 1,

Fig. 4 a plan View of the scraping device.

In these, A is an air pump of any convenient kind for ,supplying air under pressure to the hollow casin B surrounding the cooling chamber N.` Cg indicates any convenient kind of heating device or furnace, K an aspirating chamber, D the chimney from the same, through which the waste 'is a tank placed high lin any convenient position with a heating device lf3 underneath. It can however .receive y.its entire heat from the efuentga'ses of the chimney if desired.' In this tank the lead isfused.

Any well-known device for delivering lead under pressure can be used, instead of this tank placed on a high level, but I prefer this latter. In any case the lead must be the l heated sufciently to be very Huid, and be kept fluid until it is aspirated as hereafter described. It is well to have a thick layer of carbon to shieldy the lead from air currents and to prevent oxidation. In order to keep the lead hot in transit, I pass fthe lead' down to aspirator K, hereafter described, by' an iron or steel pipe F in the chimney, such pipe being exposed to the heat of the effluent gases. In the tank is a valve Z vhaving a handle Z whereby the flow of lead down this pipe may be controlled and shut olf at any time. It will be noted that the pipe being in the chimney, the temperature of the lead will be increased instead of decreased during its descent. G is a pipe coming from the pump lAto the hollow casing B, surrounding ehamber N lhereafter described and carrying cooling airto the casing where it" is heated in turn and from which it is brought by pipe C to the injector. The

injector' is shown in Fig. 3 on an enlarged scale, and.is made of cast iron or steel inV four pieces V, W, X and Y. These are carefully planed at their junctions, and-at their orifices and have preferably chipping strips at their junctions so that as the orifices wear, they can be taken down and planed away so as to again reduce the central orifices to a series of fine passages of their original size.V H is a long row of small and preferably round orifices evenly spaced for the escape of the liquid lead. I is a very much wider slit at right angles, or nearly so, bringing a blast of heated air from the pipe C.- These twox orifices or sets of orifices are parallel and 'open out into the air as close together as possible, and at right angles to the resultant line of these two jets is a second orifice J for producing a jet of hot air,

also brought from the pipe C', said orifice J being placed as near as possible to the' two other orifices H and I. A good set of dimensions is 3/8 of an inch for the air slits and a row of holes about 1/50 of an inch wide and 1/10 of an inch apart for the lead,

the exact dimensions however should, vary scraper lplate firmly fixed'on two shafts K4' passing through the conversion chamber the diameter of the carbonator, and the bottom of the chamber R3 has y.been iilled to afew inches in depth through a stoppered opening R9 above with dilute acetic acid and water, carbonio acid is also passed in. At iirst after the chamber Q hashad the. air driven out by the CO2 it is well to use toleraibly strong acetic acid and heat the bottom of chamber R3 for a time nearly to ebullition sothat there shall be plenty of acetic acid in the'carbonator Q, but care should always be taken that the material in the carbonator should never the allowed' to get wet to the touch, hence after a time the heat in the little chamber R3 is brought to about 100 Fahr. or under, the degree of heat being regulated so as to always havesome atmosphere of acetic acid and of water in thev chamber. Practically, from lk to 2% of acetic acid is desirable per weight of leadv operated on. Toward the close, however, of the operation, less acetic acid is used, and the little chamber R3 is kept colder than near the beginning. From time to time a little of the material is withdrawn from the mixer, and tested. As soon as it is found that it has reached the state of normal white lead, the supply of carbonio acid is stopped, the man-hole door opened, and the blades, which are somewhat archimedean, are allowed to empty the entire chamber, or if desirablethe motion of the stirrer is stopped, and the blades being brought to the horizontal the charge is drawn out by sera-pers resembling Dutch hoes. If impure carbonic acid be used, which is generally the case, there is an opening Q2 at the lead dust supply end of each chamber Q for the escape of waste ases.

In thus describing my invention, I do not bind myself to horizontal carbonators, as vertical or oblique ones could be used, but I prefer Ithe horizontal. In place of acetic acid there are other ,wellknown catalytes yfor this purpose that could be used, 'but they are not so advantageous as acetic acid. I would here mention that a device very similar to my injecting device has' already been used on a large scale for making extremely iine pulverulent lead and fine hair vof lead, neutral gases, such as a steam blastyor nitrogen being lused instead of air. Further, that the hydrated oxid of lead formed by my process collected in chamber N can be used in place of lithargefor nearly all purposes for which litharge or pure oxid is used at the present time. If therefore the supply of lead hydroxid be too large for the` Various cylinders Q to carbonate some of the material can be taken from the conveyer through man-hole T and used as litharge instead of being passed to chambers Q.

I declare that what I claim is v1. The process of making White lead, which consists in heating the lead to a degrec considerably above its melting point;

aspirating it through tine passages of uniform size with highly-heated air, the lead and air being brought into contact under a considerable pressure and the air being sufficient to fully oxidize the lead to monoxid;

cooling the oxidized dust thus formed; so treating it at from to 140o F. with' carbonic acid'and the fumes of acetic acid having sufficient vapor of water to cause the compound to be converted into hydrated white lead;v and at the 'same time agitating 85 ,the dust.

2. The process of making pure sublimed non-fused lead oxid applicable for making white lead by the dry process, which consists in producing an exceedingly fine spray 90 of globules of uniform size of melted lead; bringing a strong blast of hot air against the efliuent lead spray at approximately right angles thereto; and supplying further hot air until the lead is completely oxidized 9'5 to the state of monoxld. Y n 3. The process of making pure lead monoxid suitable for makingwhite lead by the dry process, which consists in forming melted lead into a fine spray 'of liquid globules 100 of practically uniform'l size; aspirating the spray withblasts of heated air, the air being of sutlicient quantity` to completely oxidize into monoxid the lead spray; continuing the thus formed dust and gases in contact with each other at a-high temperature until the lead du'st'is fully converted into monoxid; and lowering the tempera ture of the compound thus formed by a coolingl air current. v

4. The process of making pure lead monoxid applicable for making white lead by the dry process, which consists in heating the lead at a head considerably above the place" where it is afterward to be oxidized; bringing the lead down through a conduit surrounded by heated gases; passing the lead through fine orifices of equal size; exposing it at the same time to strong blasts of heated air in suficient quantity to convert the whole of the lead into monoxid; and keeping the resultant gases and dust together at a high heat until all the lead is thoroughly converted into monoxid.

5. The process of making white lead,

which consists in forming metallic lead into a sprayT of minute liquid globules of substantially yuniform size; aspirating these globules with a. quantity of hot air suiiicient to'thoroughly convert the lead into monoxid; 130

.keeping :the iesuianb im (inst anni ennien;

of gases eegeibhei nniii the ieed is coinpieieiy monoxidized; iheieeiiei @nailing fthe einen with agitation; pming the mieiiei siiii in the the form inst into n ennifeiiing eimniieen having" m agitaiing eviee; md neming ii, wiiii eaiieenie acid nn iie vapo? of a solution of acetic acid wiiiie in the inst linnn nnei aging-texi, iin-iii ii. is eenvenbefi infix@ White iefnla Wiieieiey eveny peiieie is en page@ eqnniiy in 'the gnsenns ienfgenibs.,

6. The improvement in the pi'iieess in@ making White ieani, which eonsisis in nailing 'pnie nen-fused inonoxid 0i ieaei in dust eini, andr Without ii, being' Minime/(i en enne; passing ie with agieaiion infn@ an eimospheie eoqnaining eaibnnie anni and ehe neelbie acid; ii; an@ iins eqneiiy expnsing even? paieieie 'die aefeinn of fiiie ieagenizs nnaii iis hals' nmivexi ne ehe stage White ien?,

8. The impinvemene in the process oi' making whine iead, which in mixing pine, non-fused menonid i? ieil iee from mei-diie lead., and in daba dust foi'm; and treating it, with :ign-ation, to annemosphefe nl? eniiimnie acid and from an aqueous ai, im abou-i, 90 t@ about i490 iT., until ie is feiniefi into White leed.

in Witness Wheneni9 lf have hereunto signed my naine fnis 26 day 01 Jenuaify,

i? in tnepiesenee iw@ Sni'ceeiibing Winenes-n T n iinnnnenn Enems, Q L/le-Jonmiem snintion acetic acid, ine whoie being kept 

